Three Bet and Lead Line Too Aggro Here?

[Jeffage]

50-100 game. 6 handed. I have 8 [img]/images/graemlins/diamond.gif[/img]8 [img]/images/graemlins/spade.gif[/img] UTG and raise. Folded to button who 3-bets (he seems typical). Loose SB coldcalls 125 and BB folds. I call. Three to the flop of 7-3-2 rainbow. SB checks, I bet, Button raises, SB coldcalls and I take it to three bets. Both call. Turn is an offsuit queen. SB checks, I bet. Typical, right? What's your line if raised by the button? What if button mucks and SB checkraises? Should I be morried about an overpair based on the preflop flop action (meaning should I slow down on the flop)? Results later and apologize if this is uninteresting.

Jeff